A vast number of novel proteins discovered from genome sequencing projects are creating enormous opportunities for scientists in academia and industry. Large-scale consortia and initiatives are underway to understand the structures of newly discovered proteins. Unfortunately, protein expression and purification are a major bottleneck. Bacteria are usually the first system of choice for recombinant protein expression. In phase I, LifeSensors proposed the development of a novel SUMO-fusion system to enhance expression and purification of wide variety of proteins in E. coli. The SUMO protein acts as a chaperone to promote enhanced expression as well as solubility of inclusion body proteins. SUMO fusion is also used as a handle for rapid purification of partner proteins. In phase I, a comparative study was conducted to determine the effectiveness of the SUMO expression system with other leading fusion technologies. Data showed that the SUMO system was superior to the five leading fusion systems in enhancing expression and solubility of proteins in E. coli. The phase I proposal was centered on the yeast SUMO tag and SUMO protease. In phase II, LifeSensors proposes to build on its success to broaden the scope of SUMO system by identifying new enzymes and rigorously testing the system with difficuIt-to-express proteins. Since the insect cell system has developed as a model for eukaryotic expression, it is proposed in Phase II to develop and market a SUMO system for insect cells. Development of a system that enhances expression of proteins and offers rapid purification tools at the genomic level will greatly aid post-genomic expression and protein array technologies.